There's a nice site on Penrose tiling here ==> [link] He has a program to create Penrose Tiles, and the source can be downloaded as well. I used his program for some of my older images.
==i might try smoothing the segments as well... Uh, not sure what you mean by that.
Well, its a pun allright, but its a pun on phi and five. Phi being the magic number called the Golden Section, or the Divine Proportion. Its used in Penrose tiling too. phi = (sqrt(5)+1)/2 And five, because of the 5 sided symmetry.

whoops, read too much into that pun i guess- my first impression was that of a 5-sided hive (cf. hexagonal). in my defense, i have yet to appreciate the intertwining of that mystical number and penrose's tiling process

about smoothing the segments: my first (and before your excellent link, the only) reference on how to generate penrose tilings came from wikipedia, in the form of an l-system definition. having dealt with those before (albiet in 3d) i've wondered about smoothing the segments that are formed by the turning and "go forward" process, since they usually don't join nicely the way they do in your image. so inbetween the "push" and "pop" (in l-systems it's typically [ and ] that do these) operations i smooth the constructed segments via curve subdivision...

OH, so you meant you might try smoothing the segments like what you see hear. I thought that you thought that my segments weren't smooth enough for your tastes. But then I didn't see any way to make them even smoother. The POV-ray code links I gave do have a torus_bend parm, and you can make the curves more or less bendy, but they still line up smoothly.